# Gradium Voice Cloning and Voice Design vs Speechify API Voice Cloning > Speechify API Voice Cloning scores 76.9 (BB) to Gradium Voice Cloning and Voice Design's 60.8 (C) for voice cloning. Prices, MCP, x402, uptime and agent notes side by side. - Canonical: https://www.anchorterminal.com/compare/gradium-voice-cloning-vs-speechify-voice-cloning - Markdown: https://www.anchorterminal.com/compare/gradium-voice-cloning-vs-speechify-voice-cloning.md (~5,900 tokens) - Site index for agents: https://www.anchorterminal.com/llms.txt (the key docs and every listing in one file, at most 16 MB, about 4 million tokens: https://www.anchorterminal.com/llms-full.txt) - API: https://www.anchorterminal.com/api/v1/index.json - MCP: https://www.anchorterminal.com/mcp (the whole catalogue as tools, no key) - DNS: dig +short TXT .grade.anchorterminal.com (the grade as a DNS TXT record, for a sandbox with no HTTP where names still resolve; also top., best.. and .vs.. under the zone, and the same under grade.letme.dev) - Licence: CC BY 4.0, credit Anchor Terminal and link this page (https://www.anchorterminal.com/terms/#data) - Updated: 2026-11-07 Speechify API Voice Cloning scores 76.9 (BB) on agent readiness against Gradium Voice Cloning and Voice Design's 60.8 (C), and leads in 6 of 7 scored categories. Gradium Voice Cloning and Voice Design leads on payments & pricing. Both do voice cloning. - Gradium Voice Cloning and Voice Design: grade C, 60.8/100, rank #637 of 1486. Markdown https://www.anchorterminal.com/tools/gradium-voice-cloning.md · JSON https://www.anchorterminal.com/api/v1/tools/gradium-voice-cloning.json - Speechify API Voice Cloning: grade BB, 76.9/100, rank #37 of 1486. Markdown https://www.anchorterminal.com/tools/speechify-voice-cloning.md · JSON https://www.anchorterminal.com/api/v1/tools/speechify-voice-cloning.json - Best voice cloning and custom voice APIs for AI agents: https://www.anchorterminal.com/best/voice-cloning/index.md - All 133 cloning comparisons: https://www.anchorterminal.com/compare/voice-cloning/index.md ## Which one, for what ### Gradium Voice Cloning and Voice Design (C) Good for: Builders on Gradium's TTS who want instant clones and designed voices in five European languages with EU residency. Ahead on: - Payments & pricing, 30 against 20 Also in its favour: - Free to start without a card - No incidents deducted, where Speechify API Voice Cloning loses 3 points for them Watch for: The Terms grant Gradium a licence to train its models on Client Data, and zero data retention excludes voice samples ### Speechify API Voice Cloning (BB) Good for: Best where a consent record and a published destruction schedule for voice data matter, such as cloning staff or talent voices for a product. Ahead on: - Reliability, 90 against 63 - Schema & documentation, 94 against 83 - Agent ergonomics, 97 against 67 - Security & auth, 87 against 48 - Maintenance & community, 75 against 70 - Transparency & trust, 75 against 63 Also in its favour: - Agent-ready, a grade of BB or better Watch for: No cloning on the Free plan ## Why the edge ### Security & auth: Speechify API Voice Cloning +39 - Gradium Voice Cloning and Voice Design (48): Graded for voice cloning as the other listings in this category, with consent and misuse controls in place of the read-only line and training and retention of voice data in place of the prompt-injection line. API keys per organisation in a header, revocable and able to expire, with no scopes found (20 of 30). No consent or verification field and no watermark. The Terms make the client obtain the consent of anyone whose voice is a sample and bar impersonation without explicit authorisation, and the API FAQ says explicit consent is required (6 of 20). The Terms grant Gradium a licence to use Client Data to improve its services and train its models, with no opt-out found, and zero data retention (paid plans) excludes voice samples, so samples are kept and may be used for training (2 of 15). Organisation roles and a member list, with no per-call audit log found (5 of 15). SOC 2 Type II and ISO 27001:2022 audited by A-LIGN, a trust centre and security@gradium.ai. No security.txt (404) and no bug bounty found (15 of 20). 20+6+2+5+15 = 48. - Speechify API Voice Cloning (87): Graded for voice cloning, with consent and misuse controls in place of the read-only line and training and retention of voice data in place of the prompt-injection line, since the API returns audio and IDs rather than third-party text. Service-account keys with scopes (`voices:read`, `voices:write`, `audio:all`), rotation with a grace window, and minted child keys capped at 24 hours (30). Every clone needs a single-use consent challenge, the speaker reads the phrase, and the create call is refused unless the words and speaker match, plus output watermarking with a detection endpoint (20). The trust page says Speechify never trains on customer data. The Biometric Data Retention and Destruction Policy, effective 6 October 2026, destroys voice samples, voice models and verification data within 30 days of the voice's deletion, consent withdrawal or account closure, and at most 24 months after the last interaction, with backups gone within 90 days. Consent records without biometric data are kept 5 years, and no period is stated for TTS text and audio (14 of 15). Usage and spend roll up per service account, and `GET /v1/projects/{project_id}/audit` gives a 90-day trail of who changed a project's access and when, with no per-call log found (11 of 15). security.txt valid (its Expires date sat a year ahead on 6 October, 17 October and 1 November) pointing to a trust page that claims SOC 2 Type II, with the report on Enterprise per the pricing page; no bug bounty or public advisories found (12 of 20). 30 + 20 + 14 + 11 + 12 = 87. ### Agent ergonomics: Speechify API Voice Cloning +30 - Gradium Voice Cloning and Voice Design (67): Voice objects are compact metadata (20 of 25). `GET /voices/` takes `skip` and `limit` (default 100) and since 23 October filters by `locale`, `gender` and `use_case` (20). Validation errors are structured 422 bodies, while synthesis errors arrive as plain-text HTTP 500 with a numeric code to parse (12 of 20). No idempotency key. Saving a design candidate twice answers 409, and the clone call has none (5 of 20). Three required fields with sensible defaults, and one official SDK, in Python (10 of 15). 20+20+12+5+10 = 67. - Speechify API Voice Cloning (97): Creating a voice returns a compact voice object, and `GET /v1/voices` takes `type=personal` to list only the workspace's clones (25). Voice lists page by `cursor` with `limit` up to 200 and the `type` filter (20). Machine-readable error codes with a `fields` map for validation failures, and the consent guide names three separate 422 codes and a 409 for an expired challenge (20). `Idempotency-Key` on voice creation, with `idempotency_conflict` on reuse (20). Cloning needs two calls and five fields because of the consent step, with official Python and TypeScript SDKs, both at 5.0.0 since 29 October (12 of 15). ### Reliability: Speechify API Voice Cloning +27 - Gradium Voice Cloning and Voice Design (63): Graded on the hosted voice API with the hosted lines. Atlassian Statuspage at gradium.statuspage.io with five components, one of them Voice Cloning (20). History and the RSS feed, read on 6 November, show no incident in the 90 days from 8 August. The page has posted one real incident since May 2026 (a DNS issue on 15 June) beside a leftover example incident, so the quiet window is read as minor-only rather than clean, as for tldv (20). Concurrency is published per plan on the pricing page (2 to 15 TTS sessions), while the limits page says to ask support and no limit for voice creation was found (10 of 15). No 429, Retry-After or backoff guidance was found; the errors page says to open a new connection after an error, and voice creation takes a `timeout_s` (3 of 15). No SLA in the Terms or on the pricing page (0). Instant cloning carries no beta label (10). 20+20+10+3+0+10 = 63. - Speechify API Voice Cloning (90): Status page at status.speechify.ai (Better Stack) with an API component (20). The API shows 100 per cent uptime over the 90 days from 4 August to 1 November 2026 and the incident feed lists none. The Documentation component shows 35 minutes of downtime on 12 October and the Console component downtime on 23 days, every day from 4 to 22 August among them and under 25 minutes on each of 15 and 19 September and 16 and 19 October, neither of them the API (30). Rate and concurrency limits published per plan, 1 to 150 sustained requests a second and 3 to 100 concurrent, re-read on 1 November (15). 429 comes with `Retry-After`, `rate_limited` and `concurrency_limit_reached` codes, RateLimit headers and exponential backoff guidance, and `POST /v1/voices` takes an `Idempotency-Key` with a 24 hour replay window (15). No SLA found (0). Cloning is generally available (10). 20 + 30 + 15 + 15 + 0 + 10 = 90. ### Transparency & trust: Speechify API Voice Cloning +12 - Gradium Voice Cloning and Voice Design (63): Closed service with clear terms, version of 19 October 2026, naming Gradium SAS with its Paris registration (15 of 30). The Terms allow training on Client Data, zero data retention excludes voice samples, the privacy policy gives retention criteria without periods, and a DPA is published as an exhibit. The statements agree but give no retention period for samples (15 of 30). Deprecations appear in dated release notes, with no written notice policy (10 of 20). EU and US residency is documented and selectable from the XS plan. Sub-processors sit in the trust centre, not read (12 of 20). 15+15+10+12 = 52. - Speechify API Voice Cloning (75): Closed service with clear API terms, SDKs under MIT (15 of 30). Terms (10 June 2024) and the trust page say customer data isn't used for training. The biometric data policy of 6 October 2026 sets destruction periods for voice samples, voice models and verification data, 5 years for consent records and 90 days for backups, and names service providers only by role. No public DPA (a custom DPA is listed on Enterprise), no subprocessor list and no period for TTS inputs and outputs were found (18 of 30, as for spider-cloud's stated periods with no public DPA). The September consent change was announced on 13 August, 41 days ahead, Simba 1.6 was retired at version 2026-09-21 with a dated switch on 2026-11-21 (`simba-multilingual` then served by Simba 3.5), the legacy api.sws.speechify.com host has a dated end of 19 January 2027 with Deprecation and Sunset headers, and legacy headers have a stated end date in mid-2027 (20). The regions guide of 17 October says accounts, keys, voices, usage and logs stay in the United States on every host and synthesis runs in US East or the Netherlands. No subprocessor list found (10 of 20, as for modal-sandboxes' region disclosure without a list). 15 + 18 + 20 + 10 = 63. ### Schema & documentation: Speechify API Voice Cloning +11 - Gradium Voice Cloning and Voice Design (83): Public OpenAPI 3.1 file at docs.gradium.ai/api-reference/openapi.json (25). llms.txt and Markdown pages (10). The guides say when to clone, design, enhance or localise a voice, and the custom-voice page explains the enhancement default and how to opt out (14 of 20). The clone body has `audio_file`, `name` and `language` required, a five-value language enum and typed defaults for `start_s`, `enhance` and `timeout_s` (14 of 15). curl and Python examples. The create call documents only 201 and 422, and the errors page covers synthesis, with plain-text 500 bodies (9 of 15). Routes carry no version, the OpenAPI file is 0.1.0, and release notes are dated per entry, newest 6 November 2026 (11 of 15). The API reference FAQ gives a 300-second session where the limits page says 3,000. 25+10+14+14+9+11 = 83. - Speechify API Voice Cloning (94): OpenAPI 3.1 at docs.speechify.ai/openapi.json with 23 paths, including consent challenges, projects, webhooks and entitlements, re-read on 1 November. The WebSocket input stream added on 8 October isn't among the 23 paths (25). llms.txt per section, Markdown pages and a docs-search MCP server (10). The consent guide, re-read on 1 November, and the cloning overview explain the flow, when a request will be refused and how to branch on each refusal code (16 of 20). Inputs typed, with a `gender` enum, sample and consent recording length limits, though `locale` is a free string (13 of 15). Each endpoint lists its error codes and statuses, with examples (15). Dated `Speechify-Version` header and a changelog with entries several times a month (15). 25 + 10 + 16 + 13 + 15 + 15 = 94. ### Payments & pricing: Gradium Voice Cloning and Voice Design +10 - Gradium Voice Cloning and Voice Design (30): No x402, MPP or L402 (0). Plan prices and credits are public, 1 credit a character for speech, with no dollar price per unit, as cartesia-voice-cloning is read. Creating a clone uses no credits in the docs (10). The free plan has 45,000 credits a month, 5 custom voices and Voice Design, and the site says no credit card is required. Commercial use starts on the $12 plan (20). Signup is a browser flow in Gradium Studio (0). 0+10+20+0 = 30. - Speechify API Voice Cloning (20): No x402, MPP or L402 (0). Per-unit overage prices are public, re-read on 1 November, $10, $8 and $6 per million characters by plan on Simba 3.0 and 3.2, and Simba 3.5 lists at $20, $16 and $12, billed at the lower rates until 21 November 2026 (20). The Free plan can't clone and has no voice design (0). Signup is a human browser flow (0). ## Score by category | Category | Weight | Gradium Voice Cloning and Voice Design | Speechify API Voice Cloning | Edge | | --- | --- | --- | --- | --- | | Reliability | 16% (20 this run) | 63 | 90 | Speechify API Voice Cloning +27 | | Performance | 10%, pending | pending | pending | not scored in this run | | Schema & documentation | 13% (16.2 this run) | 83 | 94 | Speechify API Voice Cloning +11 | | Agent ergonomics | 13% (16.2 this run) | 67 | 97 | Speechify API Voice Cloning +30 | | Security & auth | 14% (17.5 this run) | 48 | 87 | Speechify API Voice Cloning +39 | | Payments & pricing | 10% (12.5 this run) | 30 | 20 | Gradium Voice Cloning and Voice Design +10 | | Task success | 10%, pending | pending | pending | not scored in this run | | Maintenance & community | 7% (8.8 this run) | 70 | 75 | Speechify API Voice Cloning +5 | | Transparency & trust | 7% (8.8 this run) | 63 | 75 | Speechify API Voice Cloning +12 | | Negative events | ≤15 | 0 | -3 | | | **Total** | | **60.8 · C** | **76.9 · BB** | | ## Facts side by side | Fact | Gradium Voice Cloning and Voice Design | Speechify API Voice Cloning | | --- | --- | --- | | Kind | Model API | Model API | | Vendor | Gradium SAS | Speechify | | Hosted endpoint | `https://api.gradium.ai/api/voices/` | `https://api.speechify.ai/v1` | | Transports | HTTP, websocket | HTTP | | Auth | API key | API key | | Pricing | Freemium | Paid | | Price for voice cloning | not published | $6 per 1M characters | | x402 | no | no | | Licence | Proprietary service under Gradium's Terms of Service (version of 19 October 2026). The `gradium` Python SDK is on PyPI | MIT (SDKs) | | Read-only variant documented | no | no | | llms.txt | yes | yes | | Last release | 2026-11-06 | 2026-10-29 | | Terms last updated | no date given | 2024-06-10 | | Privacy policy last updated | no date given | 2026-07-22 | | Customer content may train models | yes | not found in the text | | Terms restrict automated access | not found in the text | yes | | Terms restrict benchmarking | not found in the text | yes | | Terms or service can change without notice | not found in the text | not found in the text | | Arbitration or class-action waiver | not found in the text | not found in the text | | Popularity | none | 3 stars, 1.9k npm/wk, 6.5k PyPI/wk | | Agent reviews | none | 3.6/5 (8) | ## How the scores have moved ### Gradium Voice Cloning and Voice Design No score change since it was listed. ### Speechify API Voice Cloning - +0.1 on 27 October 2026: checklist - +2.7 on 17 October 2026: terms, new evidence, negative event - -0.4 on 8 October 2026: checklist ## Verdicts **Gradium Voice Cloning and Voice Design.** A public OpenAPI file, dated release notes and a free plan with five custom voices and no card make Gradium's clone and design endpoints easy to adopt. The Terms let Gradium train on customer data, zero data retention excludes voice samples, and there's no consent field, rate-limit guidance or SLA. **Speechify API Voice Cloning.** Verified consent on every clone, phrase and speaker matched, recording kept, and clones speak 48 languages on Simba 3.5. No cloning on the Free plan, and cloning is refused from unnamed jurisdictions. ## Before you call either ### Gradium Voice Cloning and Voice Design 1. Send `language` on every clone. It's required and must be one of en, fr, de, es or pt and match the recording 2. Clones are enhanced by default since 23 October 2026. Pass `enhance=false` to keep the raw voice, then check `enhance` on GET 3. Pass a clone as `voice_id` in TTS, not `voice` 4. On a non-2xx synthesis reply, parse the `error from server ` prefix; 1008 means a bad or revoked key 5. Check the custom-voice allowance first. The free plan holds 5 voices shared by clones and designs ### Speechify API Voice Cloning 1. Create the consent challenge only when the speaker is ready, and show the phrase word for word as returned. It's single use and short-lived, and rewording fails the match 2. Send an `Idempotency-Key` on `POST /v1/voices` so a lost response can be replayed without spending the challenge 3. List clones with `GET /v1/voices?type=personal` so the shared catalogue doesn't fill the context 4. On 429 wait for `Retry-After`, then check `error.code` to tell a rate limit from a concurrency cap 5. Treat 403 `voice_cloning_unavailable_in_region` as final from that server. It follows the caller's IP, and no key, plan or retry lifts it ## Tutorials - [Create a consent-verified voice with Speechify](https://www.anchorterminal.com/tutorials/speechify-voice-cloning/), for Speechify API Voice Cloning ## Questions ### Which is better for AI agents, Gradium Voice Cloning and Voice Design or Speechify API Voice Cloning? Speechify API Voice Cloning scores 76.9 (BB) on agent readiness against Gradium Voice Cloning and Voice Design's 60.8 (C), and leads in 6 of 7 scored categories. Gradium Voice Cloning and Voice Design leads on payments & pricing. ### Do Gradium Voice Cloning and Voice Design and Speechify API Voice Cloning need an API key? Both need an API key. ### Can an agent call Gradium Voice Cloning and Voice Design and Speechify API Voice Cloning without installing anything? Yes. Gradium Voice Cloning and Voice Design has a hosted endpoint at https://api.gradium.ai/api/voices/ and Speechify API Voice Cloning at https://api.speechify.ai/v1. ## For agents - This comparison as JSON: https://www.anchorterminal.com/compare/gradium-voice-cloning-vs-speechify-voice-cloning.json, and with the fewest tokens: https://www.anchorterminal.com/compare/gradium-voice-cloning-vs-speechify-voice-cloning.min.md - Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {"a": "gradium-voice-cloning", "b": "speechify-voice-cloning"}`. From a terminal: `anchor compare gradium-voice-cloning speechify-voice-cloning` - Each listing in full: https://www.anchorterminal.com/api/v1/tools/gradium-voice-cloning.json and https://www.anchorterminal.com/api/v1/tools/speechify-voice-cloning.json ## Other comparisons with Gradium Voice Cloning and Voice Design or Speechify API Voice Cloning - [Cartesia Voice Cloning API + MCP vs Gradium Voice Cloning and Voice Design](https://www.anchorterminal.com/compare/cartesia-voice-cloning-vs-gradium-voice-cloning.md) - [Cartesia Voice Cloning API + MCP vs Speechify API Voice Cloning](https://www.anchorterminal.com/compare/cartesia-voice-cloning-vs-speechify-voice-cloning.md) - [ElevenLabs Voice Cloning and Voice Design API vs Gradium Voice Cloning and Voice Design](https://www.anchorterminal.com/compare/elevenlabs-voice-cloning-vs-gradium-voice-cloning.md) - [ElevenLabs Voice Cloning and Voice Design API vs Speechify API Voice Cloning](https://www.anchorterminal.com/compare/elevenlabs-voice-cloning-vs-speechify-voice-cloning.md) - [Fish Audio Voice Cloning API vs Gradium Voice Cloning and Voice Design](https://www.anchorterminal.com/compare/fish-audio-voice-cloning-vs-gradium-voice-cloning.md) - [Fish Audio Voice Cloning API vs Speechify API Voice Cloning](https://www.anchorterminal.com/compare/fish-audio-voice-cloning-vs-speechify-voice-cloning.md) - [Gradium Voice Cloning and Voice Design vs Hume Octave Voice Design and Cloning + MCP](https://www.anchorterminal.com/compare/gradium-voice-cloning-vs-hume-voice-cloning.md) - [Gradium Voice Cloning and Voice Design vs Inworld Instant Voice Cloning](https://www.anchorterminal.com/compare/gradium-voice-cloning-vs-inworld-voice-cloning.md) - [Gradium Voice Cloning and Voice Design vs MiniMax Voice Clone and Voice Design](https://www.anchorterminal.com/compare/gradium-voice-cloning-vs-minimax-voice-cloning.md) - [Gradium Voice Cloning and Voice Design vs Murf Voice Cloning API](https://www.anchorterminal.com/compare/gradium-voice-cloning-vs-murf-voice-cloning.md) - [Gradium Voice Cloning and Voice Design vs PlayHT Voice Cloning API](https://www.anchorterminal.com/compare/gradium-voice-cloning-vs-playht-voice-cloning.md) - [Gradium Voice Cloning and Voice Design vs Resemble AI Voice Cloning API](https://www.anchorterminal.com/compare/gradium-voice-cloning-vs-resemble-ai-voice-cloning.md) - [Gradium Voice Cloning and Voice Design vs Smallest.ai Instant Voice Clone](https://www.anchorterminal.com/compare/gradium-voice-cloning-vs-smallest-voice-clone.md) - [Gradium Voice Cloning and Voice Design vs Soniox Voice Cloning](https://www.anchorterminal.com/compare/gradium-voice-cloning-vs-soniox-voice-cloning.md) - [Gradium Voice Cloning and Voice Design vs Ultravox Voice Cloning](https://www.anchorterminal.com/compare/gradium-voice-cloning-vs-ultravox-voice-cloning.md) - [Gradium Voice Cloning and Voice Design vs VoiceStudio](https://www.anchorterminal.com/compare/gradium-voice-cloning-vs-voicestudio.md) - [Hume Octave Voice Design and Cloning + MCP vs Speechify API Voice Cloning](https://www.anchorterminal.com/compare/hume-voice-cloning-vs-speechify-voice-cloning.md) - [Inworld Instant Voice Cloning vs Speechify API Voice Cloning](https://www.anchorterminal.com/compare/inworld-voice-cloning-vs-speechify-voice-cloning.md) - [MiniMax Voice Clone and Voice Design vs Speechify API Voice Cloning](https://www.anchorterminal.com/compare/minimax-voice-cloning-vs-speechify-voice-cloning.md) - [Murf Voice Cloning API vs Speechify API Voice Cloning](https://www.anchorterminal.com/compare/murf-voice-cloning-vs-speechify-voice-cloning.md) - [PlayHT Voice Cloning API vs Speechify API Voice Cloning](https://www.anchorterminal.com/compare/playht-voice-cloning-vs-speechify-voice-cloning.md) - [Resemble AI Voice Cloning API vs Speechify API Voice Cloning](https://www.anchorterminal.com/compare/resemble-ai-voice-cloning-vs-speechify-voice-cloning.md) - [Smallest.ai Instant Voice Clone vs Speechify API Voice Cloning](https://www.anchorterminal.com/compare/smallest-voice-clone-vs-speechify-voice-cloning.md) - [Soniox Voice Cloning vs Speechify API Voice Cloning](https://www.anchorterminal.com/compare/soniox-voice-cloning-vs-speechify-voice-cloning.md) - [Speechify API Voice Cloning vs Ultravox Voice Cloning](https://www.anchorterminal.com/compare/speechify-voice-cloning-vs-ultravox-voice-cloning.md) - [Speechify API Voice Cloning vs VoiceStudio](https://www.anchorterminal.com/compare/speechify-voice-cloning-vs-voicestudio.md) --- Query this catalogue directly over MCP: https://www.anchorterminal.com/mcp (Streamable HTTP, no key). How: https://www.anchorterminal.com/agents/#mcp